Support Yarn PnP Imports

[DavidArchibald]

Resolves #1514 which describes the crux of the issue. Specifically imports in your svelete.config.js won't be able to resolve because they use ESM imports and Node doesn't have a loader set up.

This is my first contribution to the repo so let me know if anything doesn't fit the style etc.!

The PR itself is fairly simple but it shouldn't be merged until yarnpkg/berry#5953 is ready as otherwise yarn dlx @yarnpkg/sdks vscode won't set up the VSCode setting. Arguably more importantly if the --loader ./.pnp.loader.mjs approach is inappropriate here I'm sure they'll let me know on that PR!

[dummdidumm]

Code looks good apart from one thing - could you add that setting to the restrictedConfigurations setting in that same file further above?

[DavidArchibald]

Sounds good! Should be done.

I also realised that the ls-path setting uses hyphens and I was using camelCase so I went ahead and renamed it to runtime-args. I went ahead and force pushed the change because I figured two commits was probably overkill for this PR but maybe squashing is the norm?

[dummdidumm]

Re commits: Sqash-merging is the norm here, so don't worry about the commit history 😄

[dummdidumm]

Looks good 👍 Let me know when the changes have landed on the other end and we can merge this one

[DavidArchibald]

It's been merged in yarnpkg/berry!

[DavidArchibald]

It looks like the tests are now failing:

packages/language-server test:   1) CompletionProviderImpl
packages/language-server test:        doesnt suggest svelte auto import when already other import with same name present:
packages/language-server test:      Error: Could not find source file: '/home/runner/work/language-tools/language-tools/packages/language-server/test/plugins/typescript/testfiles/completions/ScndImport.svelte'.
packages/language-server test:       at getValidSourceFile (/home/runner/work/language-tools/language-tools/node_modules/.pnpm/[email protected]/node_modules/typescript/lib/typescript.js:141757:24)
packages/language-server test:       at Object.getCompletionsAtPosition2 [as getCompletionsAtPosition] (/home/runner/work/language-tools/language-tools/node_modules/.pnpm/[email protected]/node_modules/typescript/lib/typescript.js:142039:9)
packages/language-server test:       at CompletionsProviderImpl.getCompletions (src/plugins/typescript/features/CompletionProvider.ts:208:31)
packages/language-server test:       at async openFileToBeImported (test/plugins/typescript/features/CompletionProvider.test.ts:793:9)
packages/language-server test:       at async Context.<anonymous> (test/plugins/typescript/features/CompletionProvider.test.ts:899:9)
packages/language-server test: Initialize new ts service at  /home/runner/work/language-tools/language-tools/packages/language-server/test/plugins/typescript/testfiles/tsconfig.json
packages/language-server test: Trying to load configs for /home/runner/work/language-tools/language-tools/packages/language-server/test/plugins/typescript/testfiles
packages/language-server test: No svelte.config.js found. Using https://github.com/sveltejs/svelte-preprocess as fallback
packages/language-server test: SnapshotManager File Statistics:
packages/language-server test: Project files: 132
packages/language-server test: Svelte files: 113
packages/language-server test: From node_modules: 0
packages/language-server test: Total: 132
packages/language-server test: Failed

I'm confused how I could've changed anything that'd impact this test though because the behaviour when not configured should be identical. I suppose I reordered the flags, they used to be ["--no-lazy", "--experimental-modules", `--inspect=${port}`] and now will be ["--no-lazy", `--inspect=${port}`, "--experimental-modules"] in debug mode. I feel like that shouldn't have made a test start failing though.

[jasonlyu123]

Don't worry about this one. It's a flaky test. It failed in the master branch a few times as well. It's likely a race condition that only happened in the tests. It is not a blocking issue. I'll try to fix it later.